16 BOTANICAL GAZETTE [JANUARY 
in the ovary more removed from the ovules show diminished 
contents or may be empty, but their course can be readily 
followed in the floral tube where the protoplasm is massed into 
the deeply staining ‘‘Propfen.” The cystoids likewise remain 
long among the enlarging ovules, but their adjoined tubes, which 
are never conspicuous, soon collapse. All other functionless 
tubes seem quickly to perish in the ovary. 
The male gametophyte as represented by the pollen tube, 
therefore, both in size and in length of life becomes a conspic- 
uous generation. It is at first nourished by the stored foods of 
the spore and conducting tissue. After fertilization, with the 
growth of the ovary, connection is severed between the part in 
the floral tube and that near the micropyle, the lower end con- 
tinuing to live apparently parasitically on the embryo sac for a 
time. 
FERTILIZATION. 
The pollen tube is usually much contorted in its passage 
through the micropyle, and upon reaching the embryo sac it 
swelis out in bulbous fashion, at the same time causing one of 
the synergids to disappear. The whole region is so disturbed by 
the vigor of the tube that the fate of this cell could not be cer- 
tainly determined, but appearances indicate that the pollen tube 
may have passed into the synergid inflating it (figs. 76-82). It 
often happens that two pollen tubes pass into one ovule; in such 
cases both synergids disappear, and a favorable view of the 
embryo sac shows the two swollen, darkly staining tips of the 
pollen tubes arranged symmetrically side by side (fig. 75), as 
though growth of each had been stopped at a certain point. In 
one instance where three tubes had passed in through one 
micropyle the whole upper half of the embryo sac was filled by 
their contents. Guignard (8) has reported that in Micotiana 
Tabacum and Datura laevis the pollen tube passes into one of the 
synergids. 
The male cells were not seen in the embryo sac before fer- 
tilization. Numerous preparations showed one male nucleus in 
contact with the egg, and the fate of the second male nucleus 
was determined in a few cases when it was- found uniting with 
